Vehicle control device

ABSTRACT

A vehicle control device includes: a three-dimensional object detecting unit, an oncoming vehicle detecting unit, and an erroneous detection determination unit. The three-dimensional object detecting unit detects a three-dimensional object provided between a travel lane in which a host vehicle travels and an opposite lane in which an oncoming vehicle travels. The oncoming vehicle detecting unit detects the oncoming vehicle traveling in the opposite lane. The erroneous detection determination unit determine that the oncoming vehicle detected by the oncoming vehicle detecting unit has been erroneously detected when the oncoming vehicle detected by the oncoming vehicle detecting unit is present within a threshold range from the three-dimensional object detected by the three-dimensional object detecting unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from Japanese Patent ApplicationNo. 2017-114555 filed on Jun. 9, 2017, the entire contents of which arehereby incorporated by reference.

BACKGROUND 1. Technical Field

The present invention relates to a vehicle control device that makescontrol to avoid collision between a host vehicle and an oncomingvehicle.

2. Related Art

European Patent Application Publication (EP-A) No. 2837538 discloses atechnique that detects a center line separating a travel lane in which ahost vehicle travels from an opposite lane in which an oncoming vehicletravels and returns the host vehicle to the travel lane if the hostvehicle may collide with the oncoming vehicle when the host vehicleenters the opposite lane for passing.

SUMMARY OF THE INVENTION

An aspect of the present invention provides a vehicle control deviceincluding a three-dimensional object detecting unit, an oncoming vehicledetecting unit and an erroneous detection determination unit. Thethree-dimensional object detecting unit is configured to detect athree-dimensional object provided between a travel lane in which a hostvehicle travels and an opposite lane in which an oncoming vehicletravels. The oncoming vehicle detecting unit is configured to detect theoncoming vehicle traveling in the opposite lane. The erroneous detectiondetermination unit is configured to determine that the oncoming vehicledetected by the oncoming vehicle detecting unit has been erroneouslydetected when the oncoming vehicle detected by the oncoming vehicledetecting unit is present within a threshold range from thethree-dimensional object detected by the three-dimensional objectdetecting unit.

An aspect of the present invention provides a vehicle control deviceincluding circuitry. The circuitry is configured to detect athree-dimensional object provided between a travel lane in which a hostvehicle travels and an opposite lane in which an oncoming vehicletravels. The circuitry is configured to detect the oncoming vehicletraveling in the opposite lane. The circuitry is configured to determinethat the detected oncoming vehicle by the oncoming vehicle detectingunit has been erroneously detected when the detected oncoming vehicledetected is present within a threshold range from the detectedthree-dimensional object detected.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the structure of a vehicle.

FIG. 2 is a functional block diagram schematically illustrating thefunctions of a vehicle control device and an outside environmentrecognition device.

FIG. 3A and FIG. 3B are explanatory diagrams used to describe abrightness image and a distance image.

FIG. 4 is a flowchart illustrating control target oncoming vehicle setprocessing according to the present example.

FIG. 5 is a flowchart illustrating oncoming vehicle detection processingaccording to the present example.

FIG. 6 is a flowchart illustrating positional relationship checkprocessing according to the present example.

FIG. 7 is a flowchart illustrating control target oncoming vehicleselection processing according to the present example.

FIG. 8 illustrates a lane line detection range.

DETAILED DESCRIPTION

A preferred example of the present invention will be described withreference to the attached drawings. Dimensions, materials, specificvalues, and the like indicated in the example are only instances forfacilitating understanding of the present invention and do not limit thepresent invention unless otherwise specified. Further, elements in theexample which are not recited in a most-generic independent claim of thedisclosure are optional and may be provided on an as-needed basis. Thedrawings are schematic and are not intended to be drawn to scale. In thespecification and drawings, elements having substantially the samefunction and configuration are denoted by the same reference numeral toomit redundant explanations and elements not directly related to thepresent invention are not illustrated.

In the related art disclosed in EP-A No. 2837538, if, for instance, anoncoming vehicle is erroneously detected, control is made so that thehost vehicle is returned to the travel lane to avoid the erroneouslydetected oncoming vehicle even when the host vehicle can perform passingotherwise. Since collision between the host vehicle and an oncomingvehicle is erroneously avoided if the oncoming vehicle is erroneouslydetected in the related art disclosed in EP-A No. 2837538, collisionbetween the host vehicle and the oncoming vehicle cannot be avoidedaccurately.

It is desirable to provide a vehicle control device capable ofaccurately avoiding collision between the host vehicle and the oncomingvehicle.

In recent years, a vehicle with a so-called collision avoidance functionhas come into widespread use in which an onboard camera mounted in thevehicle images the road environment in front of the host vehicle,identifies other vehicles based on color information and positioninformation in the image, and avoids collision with the identified othervehicles or keeps a safe inter-vehicle distance from other vehicles(ACC: Adaptive Cruise Control). The following details a vehicle havingan outside environment recognition device that recognizes such anoutside environment and a vehicle control device that makes control foravoiding collision between a vehicle (host vehicle) and other vehicles(oncoming vehicles). Note that the example describes a case of a trafficsystem whereby vehicles move on the left side of a road.

FIG. 1 illustrates the structure of a vehicle (host vehicle) 100. InFIG. 1, the solid arrows indicate the directions of transmission of dataand the dashed arrows indicate the directions of transmission of controlsignals. As illustrated in FIG. 1, the vehicle 100 is an automobilehaving an engine 102. Although the drive source is an engine here, thedrive source may be a motor generator, or an engine and a motorgenerator.

A crankshaft 104 of the engine 102 is coupled to a front wheel sidepropeller shaft 108 via a transmission 106. The front wheel sidepropeller shaft 108 has one end to which a front wheel side drive shaft112 is coupled via a front differential gear 110 and the other end towhich a rear wheel side propeller shaft 116 is coupled via an electroniccontrol coupling 114. Front wheels 120 are coupled to both ends of thefront wheel side drive shaft 112.

A rear wheel side drive shaft 122 is coupled to the rear end of the rearwheel side propeller shaft 116 opposite to the electronic controlcoupling 114 via a rear differential gear 118. Rear wheels 130 arecoupled to both ends of the rear wheel side drive shaft 122.

Accordingly, in the vehicle 100, a torque output from the engine 102 istransmitted to the front wheels 120 via the crankshaft 104, thetransmission 106, the front wheel side propeller shaft 108, the frontdifferential gear 110, and the front wheel side drive shaft 112.

In addition, in the vehicle 100, a torque output from the engine 102 istransmitted to the rear wheels 130 via the crankshaft 104, thetransmission 106, the front wheel side propeller shaft 108, theelectronic control coupling 114, the rear wheel side propeller shaft116, the rear differential gear 118, and the rear wheel side drive shaft122. The electronic control coupling 114 is capable of adjusting theratio between the torque (driving force) transmitted to the front wheels120 and the torque (driving force) transmitted to the rear wheels 130according to the travel state and an instruction from the driver.

A steering mechanism 132 changes the angle of the front wheels 120 withrespect to the vehicle body according to the steering angle of asteering wheel operated by the driver. In addition, the steeringmechanism 132 has a steering motor (not illustrated) and changes theangle of the front wheels 120 with respect to the vehicle body by beingdriven by the steering motor according to control by a steering controlunit 212 described later when control is made to avoid collision betweenthe vehicle 100 and an oncoming vehicle.

In addition, the vehicle 100 is provided with an ECU 134. The ECU 134 isconfigured by a semiconductor integrated circuit including a centralprocessing unit (CPU), a ROM in which a program and the like are stored,a RAM as a work area, and the like and makes centralized control of theengine 102.

In addition, the vehicle 100 is provided with a vehicle control device140. The vehicle control device 140 is configured by a semiconductorintegrated circuit including a central processing unit (CPU), a ROM inwhich a program and the like are stored, a RAM as a work area, and thelike and makes centralized control of individual units of the vehicle100. The vehicle control device 140 is coupled to an accelerator pedalsensor 142, a brake pedal sensor 144, a vehicle speed sensor 146, arotation speed sensor 148, an angular velocity sensor 150, and asteering angle sensor 152 and receives signals indicating the valuesdetected by these sensors at predetermined intervals. In addition, thevehicle control device 140 is coupled to a HMI (Human Machine Interface)154, a GNSS (Global Navigation Satellite System) 156, an inter-vehiclecommunication device 158, and an outside environment recognition device172, which will be described later, receives signals (information)transmitted from these devices, and transmits signals (information) tothese devices.

The accelerator pedal sensor 142 detects the amount of accelerator pedaldepression (amount of accelerator depression) and transmits anaccelerator depression amount signal indicating the amount ofaccelerator depression to the vehicle control device 140. The brakepedal sensor 144 detects the amount of brake pedal depression (amount ofbrake depression) and transmits a brake depression amount signalindicating the amount of brake depression to the vehicle control device140. The vehicle speed sensor 146 detects the vehicle speed of thevehicle 100 and transmits a vehicle speed signal indicating the vehiclespeed to the vehicle control device 140. The rotation speed sensor 148detects the rotation speed of the engine 102 and transmits a rotationspeed signal indicating the rotation speed to the vehicle control device140. The angular velocity sensor 150 detects the angular velocity of thefront wheels 120 and transmits an angular velocity signal indicating theangular velocity to the vehicle control device 140. The steering anglesensor 152 detects the steering angle of the steering wheel andtransmits a steering angle signal indicating the steering angle of thesteering wheel to the vehicle control device 140.

The ECU 134 is coupled to the engine 102 and transmits a control signalto the engine 102. In addition, the vehicle control device 140 iscoupled to a brake 160 and the electronic control coupling 114 andtransmits control signals to the brake 160 and the electronic controlcoupling 114.

The ECU 134 receives, from the vehicle control device 140, theaccelerator depression amount signal transmitted from the acceleratorpedal sensor 142 and the rotation speed signal indicating the rotationspeed of the engine 102 transmitted from the rotation speed sensor 148.The ECU 134 derives the target torque and the target rotation speed ofthe engine 102 with reference to a map stored in advance, based on theaccelerator depression amount signal and the rotation speed signal.Then, the ECU 134 drives the engine 102 so that the derived targettorque and the derived target rotation speed are achieved.

The HMI 154 is an interface between the driver and the vehicle equipmentand is a device that reports danger to the driver of the vehicle 100when, for instance, the vehicle 100 may collide with an oncomingvehicle. A monitor, a speaker, or the like may be used as the HMI 154.For instance, when receiving a danger notification signal (information)from the vehicle control device 140, the HMI 154 reports the danger tothe driver of the vehicle 100 by displaying the content of the dangernotification in a monitor and giving an alarm sound or a messageconcerning the risk report via a speaker. In addition, an operating unitis provided by which the driver can set the traffic division (right handor left hand) in which the vehicle 100 travels, as described later.

The GNSS 156 is a device that detects the position information of thevehicle 100. This GNSS 156 detects the information of the latitude andlongitude of the vehicle 100 as the position information of the vehicle100 via a GNSS antenna (not illustrated). In addition, the GNSS 156 candetect information about the travel direction of the vehicle 100 basedon the information of the latitude and longitude of the vehicle 100.

The inter-vehicle communication device 158 is a device that exchangesinformation with oncoming vehicles on the periphery of the vehicle 100.The inter-vehicle communication device 158 exchanges information withoncoming vehicles on the periphery of the vehicle 100 by transmittinginformation about the vehicle 100 to oncoming vehicles via communicationand receiving (detecting) information about oncoming vehicles viacommunication. In the present example, the inter-vehicle communicationdevice 158 transmits the information of the position, speed, and traveldirection of the vehicle 100 as the information about the vehicle 100and receives the information of the positions, speeds, and traveldirections of oncoming vehicles as the information about the oncomingvehicles.

In addition, the vehicle 100 is provided with imaging apparatuses 170and the outside environment recognition device 172. Each of the imagingapparatuses 170 includes imaging devices such as CCDs (Charge-CoupledDevice) and CMOSs (Complementary Metal-Oxide Semiconductor) and iscapable of generating a color image or a monochrome image by taking animage of the environment corresponding to the front of the vehicle 100.Color values are a set of values including one brightness value (Y) andtwo color difference values (UV) or including three hues (R (red), G(green), B (blue)). Color images and monochrome images taken by theimaging apparatus 170 are referred to as brightness images here todistinguish them from distance images, which will be described later.

In addition, the imaging apparatuses 170 are disposed separately fromeach other substantially in the horizontal direction on the front sidein the travel direction of the vehicle 100 so that the optical axes ofthe two imaging apparatuses 170 are substantially parallel to eachother. The imaging apparatus 170 continuously generates image dataobtained by imaging particular objects present in the detection area infront of the vehicle 100 for each of, for instance, 1/60 second frames(60 fps).

The outside environment recognition device 172 obtains image data fromthe two imaging apparatuses 170, derives the parallax by using so-calledpattern matching, and generates a distance image by associating thederived parallax information (equivalent to the relative distancedescribed later) with the image data. A brightness image and a distanceimage will be described in detail later. In addition, the outsideenvironment recognition device 172 identifies the particular object towhich the target object displayed in the detection area in front of thevehicle 100 corresponds by using the brightness value (color value)based on a brightness image and the relative distance informationrelative to the vehicle 100 based on a distance image. The particularobjects to be recognized include not only an object that independentlyexists, such as a vehicle, a person (pedestrian), a traffic light, aroad (traveling path), a lane line of a road, or a guardrail, but alsoan object identifiable as a part of an object that independently exists,such as a tail lamp, a turn signal, or a lamp of a traffic light.Individual functional units in the following example perform individualprocesses for each frame when such image data is updated.

The structure of the outside environment recognition device 172 will bedescribed in detail below. The following details the procedure foridentifying particular objects such as oncoming vehicles and lane linespositioned in front (in the travel direction) of the host vehiclecharacteristic of the present example and components not characteristicof the present example are not described.

FIG. 2 is a functional block diagram schematically illustrating thefunctions of the vehicle control device 140 and the outside environmentrecognition device 172. As illustrated in FIG. 2, the outsideenvironment recognition device 172 includes an interface unit 180, adata retaining unit 182, and a centralized control unit 184.

The interface unit 180 is an interface through which information isexchanged bidirectionally with the imaging apparatus 170 and the vehiclecontrol device 140. The data retaining unit 182 includes a RAM, a flashmemory, a HDD, and the like, retains various kinds of informationrequired for processing by the functional units described below, andtemporarily retains image data received from the imaging apparatus 170.

The centralized control unit 184 is configured by a semiconductorintegrated circuit including a central processing unit (CPU), a ROM inwhich a program and the like are stored, a RAM as a work area, and thelike and controls the interface unit 180, the data retaining unit 182,and the like via a system bus 186. In addition, in the present example,the centralized control unit 184 also functions as an image processingunit 190, a three-dimensional position information generation unit 192,a grouping unit 194, a road identifying unit 196, a lane line detectingunit 198, a mobile object identifying unit 200, and a three-dimensionalobject identifying unit 202. The processing by these functional unitswill be described below.

The image processing unit 190 obtains image data from the two imagingapparatuses 170 and derives the parallax using so-called patternmatching in which the block corresponding to a block (for instance, anarray having four horizontal pixels and four vertical pixels) extractedarbitrarily from one image data is searched for in the other image data.Here, “horizontal” represents the screen horizontal direction (directionalong the longer side) of a taken brightness image and “vertical”represents the screen vertical direction (direction along the shorterside) of the taken brightness image.

This pattern matching is considered to compare the brightness values(Y-color difference signals) for each block indicating any imageposition between two pieces of image data. For instance, there aremethods such as SAD (Sum of Absolute Difference) that takes thedifference between brightness values, SSD (Sum of Squared intensityDifference) that uses the square of the difference, and NCC (NormalizedCross Correlation) that takes the similarity of variance values obtainedby subtracting the average value from the brightness values ofindividual pixels. The image processing unit 190 performs such parallaxderiving processing for each block on all blocks displayed in thedetection area (having, for instance, 600 horizontal pixels and 180vertical pixels). Although a block has four horizontal pixels and fourvertical pixels here, a block may have any number of pixels.

However, although the image processing unit 190 can derive the parallaxfor each block that is the detection resolution unit, the imageprocessing unit 190 cannot recognize the target object to which theblock belongs. Accordingly, parallax information is derivedindependently for each detection resolution unit (referred to below as athree-dimensional part) such as, for instance, a block in the detectionarea, not for each target object. The image in which the parallaxinformation (equivalent to the relative distance information) derived inthis way is associated with the three-dimensional parts of image data isreferred to as a distance image.

FIG. 3 A and FIG. 3B are explanatory diagrams used to describe abrightness image 300 and a distance image 302. It is assumed that, forinstance, the brightness image (image data) 300 as illustrated in FIG.3A is generated through the two imaging apparatuses 170 for a detectionarea 304. However, only one of the two brightness image 300 isschematically illustrated here for ease of understanding. In the presentexample, the image processing unit 190 obtains the parallax for each ofthree-dimensional parts from the brightness image 300 and forms thedistance image 302 as illustrated in FIG. 3B. Each of three-dimensionalparts in the distance image 302 is associated with the parallax of thethree-dimensional part. For convenience of description, thethree-dimensional parts for which parallaxes have been derived areindicated by black dots here.

Returning to FIG. 2, the three-dimensional position informationgeneration unit 192 converts the parallax information for each ofthree-dimensional parts in the detection area 304 to three-dimensionalposition information including the horizontal distance, the height, andthe relative distance using the so-called stereo method based on thedistance image 302 generated by the image processing unit 190. Thestereo method derives the relative distance of a three-dimensional partwith respect to the imaging apparatus 170 based on the parallax of athree-dimensional part using a triangular surveying method. At thistime, the three-dimensional position information generation unit 192derives the height of a three-dimensional part from the road surfacebased on the relative distance of the three-dimensional part and thedistance on the distance image 302 from the point on the road surfacedistant by the same relative distance as in the three-dimensional partto the three-dimensional part.

The grouping unit 194 assumes that the three-dimensional parts for whichthe differences of three-dimensional positions (horizontal distances x,heights y, and relative distances z) are present within a predeterminedrange (for instance 0.1 m) in the distance image 302 correspond to thesame particular object and groups these three-dimensional parts. In thisway, a target object that is a set of three-dimensional parts isgenerated. The range of grouping described above is represented by adistance in a real space and can be set to any value by themanufacturer. In addition, for three-dimensional parts newly added bygrouping, the grouping unit 194 further groups the three-dimensionalparts for which the differences of the horizontal distances x, thedifferences of heights y, and the differences of relative distances zare present within a predetermined range using the addedthree-dimensional parts as base points. Consequently, allthree-dimensional parts that can be assumed to be the same particularobject are grouped into a target object.

When the target object meets a predetermined condition corresponding toa road (for instance, when the positional relationship with lane lines,other vehicles, and road side target objects such as guardrailscorresponds to a particular object “road”), the road identifying unit196 identifies the target object as the particular object “road”.

The lane line detecting unit 198 identifies lane lines on the surface ofthe identified road based on the three-dimensional positions in thedistance image 302 and the brightness values (color values) based on thebrightness image 300. The target to be identified includes a yellowline. In addition, a dashed lane line and a dashed yellow line are alsotargets to be identified. In the following description, a lane line alsoincludes a yellow line and a dashed line (dashed lane line and dashedyellow line).

For instance, the lane line detecting unit 198 detects, as a lane line,an object that is grouped on the road surface by the grouping unit 194,has a color within the preset brightness range of a lane line, andstretches toward the front of a travel path on the road surface.Although the lane line detecting unit 198 detects a lane line based onimage data from the imaging apparatuses 170 here, the lane linedetecting unit 198 may detect a lane line by another way such as, forinstance, a laser.

When the target object obtained by grouping meets a predeterminedcondition corresponding to a vehicle (for instance, the target object ispositioned on a road and the entire size of the target objectcorresponds to the size of the particular object “vehicle”), the mobileobject identifying unit 200 identifies the target object as a particularobject “another vehicle”.

When the target object obtained by grouping meets a predeterminedcondition corresponding to a wall, the three-dimensional objectidentifying unit 202 identifies the target object as a particular object“wall”. When the difference of three-dimensional positions (horizontaldistances x, heights y, and relative distances z) is present within apredetermined range (for instance, 0.1 m), the height y is equal to ormore than a predetermined height, and the target object stretches towardthe front of a travel path on the road surface, the three-dimensionalobject identifying unit 202 identifies the target object as a “wall”. Inthe present example, a wall is provided in the center divider of theroad, has a height equal to or more than a predetermined height, andstretches toward the front of a travel path on the road surface.Although the three-dimensional object identifying unit 202 identifies awall provided in the center divider of the road in the present example,the three-dimensional object identifying unit 202 may identify athree-dimensional object such as a tree provided in the center dividerof the road.

In addition, the vehicle control device 140 functions as a brakingcontrol unit 210, the steering control unit 212, a center line detectingunit 214, an oncoming vehicle detecting unit 216, a predicted timederiving unit 218, a distance deriving unit 220, a control targetoncoming vehicle selecting unit 222, a three-dimensional objectdetecting unit 224, and an erroneous detection determination unit 226.

When receiving the brake depression amount signal from the brake pedalsensor 144, the braking control unit 210 brakes the vehicle 100 bycontrolling the brake 160 according to the brake depression amountsignal.

The steering control unit 212 controls the steering mechanism 132according to the accelerator depression amount signal, the brakedepression amount signal, the vehicle speed signal, a rotation anglesignal for the engine 102, the angular velocity signal for the frontwheels 120, and the steering angle signal.

The center line detecting unit 214 detects the center line thatseparates the travel lane in which the vehicle 100 travels from theopposite lane in which oncoming vehicles travel, based on the lane lineson the road detected by the lane line detecting unit 198. For instance,the center line detecting unit 214 detects the lane line closest to thecenter of the road as the center line based on the road identified bythe road identifying unit 196 and the lane lines on the road detected bythe lane line detecting unit 198. In addition, the center line detectingunit 214 identifies the side on which the vehicle 100 is positioned asthe travel lane based on the center line and identifies the sideopposite to the side on which the vehicle 100 is positioned as theopposite lane based on the center line.

The oncoming vehicle detecting unit 216 detects oncoming vehicles thattravel in the opposite lane. How to specifically detect oncomingvehicles will be described later.

The predicted time deriving unit 218 derives the collision predictedtime that elapses before the vehicle 100 collides with an oncomingvehicle. Specifically, the predicted time deriving unit 218 obtains theposition and the travel direction of the vehicle 100 based on theinformation obtained from the GNSS 156 and obtains the speed of thevehicle 100 based on the information obtained from the vehicle speedsensor 146. In addition, the predicted time deriving unit 218 derivesthe position, the speed, and the travel direction of the oncomingvehicle based on the obtained information of the vehicle 100 and theinformation (distance image described above) of the oncoming vehicledetected by the oncoming vehicle detecting unit 216. Then, the predictedtime deriving unit 218 derives the collision predicted time that elapsesbefore the oncoming vehicle reaches the vehicle 100 based on theposition, the speed, and the travel direction of the oncoming vehicleand the position, the speed, and the travel direction of the vehicle100. The predicted time deriving unit 218 derives the time that elapsesbefore the oncoming vehicle passes the vehicle 100. For instance, thepredicted time deriving unit 218 derives the time that elapses beforethe oncoming vehicle reaches the line extending orthogonally to thetravel direction of the vehicle 100 from the front end in the traveldirection.

The distance deriving unit 220 derives a first distance between thevehicle 100 and the oncoming vehicle in the travel direction of thevehicle 100 and a second distance between the vehicle 100 and theoncoming vehicle in the direction orthogonal to the travel direction ofthe vehicle 100. Specifically, the distance deriving unit 220 obtainsthe position and the travel direction of the vehicle 100 based on theinformation obtained from the GNSS 156. In addition, the distancederiving unit 220 derives the position and the travel direction of theoncoming vehicle based on the obtained information of the vehicle 100and the information (distance image described above) of the oncomingvehicle obtained by the oncoming vehicle detecting unit 216. Then, thedistance deriving unit 220 derives the first distance and the seconddistance described above based on the position and the travel directionof the oncoming vehicle and the position and the travel direction of thevehicle 100.

The control target oncoming vehicle selecting unit 222 selects thecontrol target oncoming vehicle for which collision with the vehicle 100is avoided. How to specifically select the control target oncomingvehicle will be described later.

The three-dimensional object detecting unit 224 detects athree-dimensional object (wall or tree) provided between the travel lanein which the vehicle 100 travels and the opposite lane in which theoncoming vehicle travels. Specifically, the three-dimensional objectdetecting unit 224 detects a wall (or tree) close to the opposite laneamong the walls (or trees) identified by the three-dimensional objectidentifying unit 202 based on the information of the traffic divisionset and input by the driver.

The erroneous detection determination unit 226 determines whether theoncoming vehicle detected by the oncoming vehicle detecting unit 216 hasbeen erroneously detected. How to specifically determine erroneousdetection will be specifically described later.

FIG. 4 is a flowchart illustrating control target oncoming vehicle setprocessing according to the present example.

The control target oncoming vehicle selecting unit 222 first obtainsinformation about the traffic division from the HMI 154. The HMI 154 isconfigured so that the driver can perform travel lane customizationswitching. The driver can input information about a traffic division tothe HMI 154 by performing travel lane customization switching inadvance.

The control target oncoming vehicle selecting unit 222 determineswhether the traffic division is set to the right hand based on theinformation about the traffic division obtained from the HMI 154 (stepS401). When the traffic division is the right hand, the processingproceeds to step S403. When the traffic division is the left hand, theprocessing proceeds to step S402.

When the traffic division is the left hand (NO in step S401), thecontrol target oncoming vehicle selecting unit 222 determines whether alane line has been detected on the right side of the vehicle 100 (stepS402). When a lane line has been detected on the right side of thevehicle 100, the processing proceeds to step S404. When no lane line isdetected on the right side of the vehicle 100, the processing proceedsto step S411.

When the traffic division is the right hand (YES in step S401), thecontrol target oncoming vehicle selecting unit 222 determines whether alane line has been detected on the left side of the vehicle 100 (stepS403). When a lane line has been detected on the left side of thevehicle 100, the processing proceeds to step S404. When no lane line isdetected on the left side of the vehicle 100, the processing proceeds tostep S411.

When step S402 produces a YES result or step S403 produces a YES result,the control target oncoming vehicle selecting unit 222 causes theoncoming vehicle detecting unit 216 to perform oncoming vehicledetection processing.

FIG. 5 is a flowchart illustrating oncoming vehicle detection processingaccording to the present example.

The oncoming vehicle detecting unit 216 first derives the speed of thetarget object based on the information (distance image described above)of the target object identified by the mobile object identifying unit200. Then, the oncoming vehicle detecting unit 216 checks whether thespeed (oncoming vehicle speed) of the target object is equal to or morethan a predetermined speed (for instance, 15 km/h or more) (step S501).When the speed of the target object is less than the predeterminedspeed, since the target object is considered to travel at a low speed orbe stopped, the target object traveling at less than the predeterminedspeed is determined not to be the oncoming vehicle for which collisionwith the vehicle 100 is avoided.

Based on the information of the target object identified by the mobileobject identifying unit 200, the oncoming vehicle detecting unit 216checks whether the detection count of the identified target object isequal to or more than a predetermined count (step S502). Thepredetermined count changes depending on the position (or the distancefrom the vehicle 100 to the target object) or the speed of theidentified target object. When the detection count of the target objectis less than the predetermined count, since the target object was likelyto be erroneously detected, the target object detected at less than thepredetermined count is determined not to be the oncoming vehicle forwhich collision with the vehicle 100 is avoided.

The oncoming vehicle detecting unit 216 checks whether the size of thetarget object is equal to or more than a predetermined size based on theinformation of the target object identified by the mobile objectidentifying unit 200 (step S503). Specifically, the oncoming vehicledetecting unit 216 checks the vertical length (height), the horizontallength (width), and the area of the target object and checks whetherthese values are equal to or more than the predetermined size. Thepredetermined size changes depending on the position (or the distancefrom the vehicle 100 to the target object) of the target object. Inaddition, the predetermined size also changes depending on the outsideenvironment (for instance, evening or night) of the vehicle 100. Whenthe size of the target object is less than the predetermined size, sincethe target object is determined not to have the vehicle size, the targetobject having less than the predetermined size is determined not to bethe oncoming vehicle for which collision with the vehicle 100 isavoided.

The oncoming vehicle detecting unit 216 checks whether the aspect ratioof the target object falls within a predetermined range based on theinformation of the target object identified by the mobile objectidentifying unit 200 (step S504). Specifically, the oncoming vehicledetecting unit 216 checks the ratio between the vertical length (height)and the horizontal length (width) of the target object and checkswhether this ratio falls within the predetermined range. When the aspectratio of the target object falls outside the predetermined range, sincethe target object is likely to be a target object other than a vehicle,the target object falling outside the predetermined range is determinednot to be the oncoming vehicle for which collision with the vehicle 100is avoided.

The oncoming vehicle detecting unit 216 checks whether the parallaxdensity of the target object falls within a predetermined density rangebased on the information of the target object identified by the mobileobject identifying unit 200 (step S505). The parallax density isobtained by dividing the number of distance points by the horizontalwidth (the screen horizontal direction (direction along the longer side)of the distance image). The predetermined density range is the range ofactually measured values obtained by experiment. When the parallaxdensity of the target object falls outside the predetermined densityrange, since the target object is likely to be a target object otherthan a vehicle, the target object falling outside the predetermineddensity range is determined not to be the oncoming vehicle for whichcollision with the vehicle 100 is avoided.

The oncoming vehicle detecting unit 216 checks whether the inclinationof the target object is equal to or less than a predetermined angle (forinstance, within 45 degrees) based on the information of the targetobject identified by the mobile object identifying unit 200 (step S506).The inclination of the target object is the angle formed by the lineextending in the travel direction of the vehicle 100 and the linebetween the vehicle 100 and the target object. When the inclination ofthe target object is more than the predetermined angle, the targetobject is determined to be a vehicle that is meeting the opposite laneor going away from the opposite lane while moving orthogonally to thedirection in which the opposite lane extends, and the target objecthaving an angle more than the predetermined angle is determined not tobe the oncoming vehicle for which collision with the vehicle 100 isavoided.

The erroneous detection determination unit 226 checks the positionalrelationship between the wall detected by the three-dimensional objectdetecting unit 224 and the oncoming vehicle (step S507). The processingin step S507 for checking the positional relationship between the walland the oncoming vehicle will be described below with reference to FIG.6.

FIG. 6 is a flowchart illustrating positional relationship checkprocessing according to the present example.

The three-dimensional object detecting unit 224 first obtainsinformation about the traffic division from the HMI 154 and determineswhether the traffic division is set to the right hand (step S601). Whenthe traffic division is the right hand, the processing proceeds to stepS603. When the traffic division is the left hand, the processingproceeds to step S602.

When the traffic division is the left hand (NO in step S601), thethree-dimensional object detecting unit 224 determines whether a wallhas been detected on the right side of the vehicle 100 (step S602). Whena wall has been detected on the right side of the vehicle 100, theprocessing proceeds to step S604. When no wall has been detected on theright side of the vehicle 100, the processing proceeds to step S609.

When the traffic division is the right hand (YES in step S601), thethree-dimensional object detecting unit 224 determines whether a wallhas been detected on the left side of the vehicle 100 (step S603). Whena wall has been detected on the left side of the vehicle 100, theprocessing proceeds to step S604. When no wall has been detected on theleft side of the vehicle 100, the processing proceeds to step S609.

The erroneous detection determination unit 226 divides the wall detectedby the three-dimensional object detecting unit 224 by a segment valueand obtains the start point and the end point of the wall (step S604).The segment value is obtained based on the maximum distance in thetravel direction of the vehicle 100 that can be detected by the outsideenvironment recognition device 172. In the present example, a wall isdivided by 4096 mm (segment value) and the start point and the end pointof the wall are obtained based on the segment value. The start point andthe end point of the wall may be obtained based on the wall informationdetected in the past. For instance, the wall detected currently may beinterpolated by using the wall detected in the past in consideration ofthe position, the travel direction, and the vehicle speed of the vehicle100.

The erroneous detection determination unit 226 determines whether theoncoming vehicle is present between the start point and the end point ofthe segment value of the wall based on the information of the oncomingvehicle identified by the mobile object identifying unit 200 (stepS605). When the oncoming vehicle is present between the start point andthe end point of the segment value of the wall, the processing proceedsto step S606. When the oncoming vehicle is not present between the startpoint and the end point of the segment value of the wall, the processingproceeds to step S609.

When the oncoming vehicle is present between the start point and the endpoint of the segment value of the wall (YES in step S605), the erroneousdetection determination unit 226 obtains the longitudinal position(position in the travel direction of the vehicle 100) and the lateralposition (position in the direction orthogonal to the travel directionof the vehicle 100) of the oncoming vehicle. In addition, the erroneousdetection determination unit 226 obtains the lateral position of thewall in the longitudinal position corresponding to the longitudinalposition of the oncoming vehicle (step S606).

The erroneous detection determination unit 226 compares the obtainedlateral position of the oncoming vehicle with the obtained lateralposition of the wall and determines whether the lateral position of theoncoming vehicle is present within the threshold range from the lateralposition of the wall (step S607). The threshold range is, for instance,500 mm. When the lateral position of the oncoming vehicle is presentwithin the threshold range from the lateral position of the wall, it isdetermined that part of the wall has been erroneously detected as theoncoming vehicle due to error or the like in the brightness image 300taken by the imaging apparatuses 170. When the lateral position of theoncoming vehicle is present within the threshold range from the lateralposition of the wall, the processing proceeds to step S608. When thelateral position is present outside the threshold range, the processingproceeds to step S609.

When the lateral position of the oncoming vehicle is present within thethreshold range from the lateral position of the wall (YES in stepS607), the erroneous detection determination unit 226 determines thatthe detected oncoming vehicle has been erroneously detected (step S608)and ends positional relationship check processing.

When steps S602, S603, S605, and S607 produce NO results, the erroneousdetection determination unit 226 determines that the detected oncomingvehicle has not been erroneously detected (step S609) and endspositional relationship check processing.

Returning to FIG. 5, the oncoming vehicle detecting unit 216 determineswhether all of the conditions in steps S501 to S507 are met (step S508).When all of the conditions in steps S501 to S507 are met, the processingproceeds to step S509. When any of the conditions in steps S501 to S507is not met, the processing proceeds to step S510.

When all of the conditions in steps S501 to S507 are met (YES in stepS508), the oncoming vehicle detecting unit 216 determines that theoncoming vehicle has been detected (step S509) and finishes the oncomingvehicle detection processing.

When any of the conditions in steps S501 to S507 is not met (NO in stepS508), the oncoming vehicle detecting unit 216 determines that theoncoming vehicle has not been detected (undetected) (step S510) andfinishes the oncoming vehicle detection processing.

Returning to FIG. 4, the control target oncoming vehicle selecting unit222 determines whether the oncoming vehicle has been detected (stepS405). When the oncoming vehicle has been detected, the processingproceeds to step S406. When the oncoming vehicle has not been detected,the processing proceeds to step S411.

When the oncoming vehicle has been detected (YES in step S405), thecontrol target oncoming vehicle selecting unit 222 obtains a collisionpredicted time (TTC: Time To Collision), which is the time that elapsesbefore the vehicle 100 collides with the oncoming vehicle, from thepredicted time deriving unit 218. Then, a determination is made as towhether the TTC is equal to or less than a predetermined time (forinstance, within 1.5 seconds) (step S406) When the TTC is equal to orless than the predetermined time, the processing proceeds to step S407.When the TTC is more than the predetermined time, the processingproceeds to step S411.

When the TTC is equal to or less than the predetermined time (YES instep S406), the control target oncoming vehicle selecting unit 222determines whether the distance between the vehicle 100 and the oncomingvehicle in the travel direction of the vehicle 100 is equal to or lessthan a lane line detection distance (step S407). Here, the controltarget oncoming vehicle selecting unit 222 obtains the length (distance)of the lane line (center line) detected by the lane line detecting unit198 in the travel direction of the vehicle 100. Then, the length of thelane line detected by the lane line detecting unit 198 is compared withthe distance between the vehicle 100 and the oncoming vehicle. When thedistance between the vehicle 100 and the oncoming vehicle is longer thanthe distance within which a lane line is detectable, since the oncomingvehicle is not reliably recognized as an oncoming vehicle, the controltarget oncoming vehicle selecting unit 222 determines that the oncomingvehicle is not an oncoming vehicle. When the lane line is equal to orshorter than the detectable distance, the processing proceeds to stepS408. When the lane line is longer than the detectable distance, theprocessing proceeds to step S411.

When the distance between the vehicle 100 and the oncoming vehicle isequal to or less than the lane line detection distance (YES in stepS407), the control target oncoming vehicle selecting unit 222 performscontrol target oncoming vehicle selection processing (step S408).

FIG. 7 is a flowchart illustrating control target oncoming vehicleselection processing according to the present example.

The control target oncoming vehicle selecting unit 222 determineswhether the oncoming vehicle is present within the lane line detectionrange derived based on the center line (step S701). When the oncomingvehicle is present within the lane line detection range, the processingproceeds to step S702. When the oncoming vehicle is present outside thelane line detection range, the processing proceeds to step S705.

Next, the lane line detection range will be described. FIG. 8illustrates a lane line detection range A. As illustrated in FIG. 8, thevehicle 100 travels in a travel lane S1 of a road S having one lane foreach way and an oncoming vehicle 400 travels in an opposite lane S2 ofthe road S. The travel lane S1 is bordered by a lane line H1 (vehicletravel zone border line of the travel lane S1) and a lane line H2(center line). The opposite lane S2 is bordered by a lane line H3(vehicle travel zone border line of the opposite lane S2) and the laneline H2. The lane line detection range A is derived based on the laneline H2 (center line) and is, for instance, an area adjacent to the laneline H2 in the opposite lane S2 and within a predetermined distance L(for instance, within 1.4 m) from the lane line H2.

Returning to FIG. 7, when the oncoming vehicle is present within thelane line detection range A (YES in step S701), the control targetoncoming vehicle selecting unit 222 determines whether a plurality ofoncoming vehicles is present in the lane line detection range A (stepS702). When a plurality of oncoming vehicles is present, the processingproceeds to step S703. When a plurality of oncoming vehicles is notpresent (that is, only one oncoming vehicle is present), the processingproceeds to step S704.

When a plurality of oncoming vehicles is present within the lane linedetection range A (YES in step S702), the control target oncomingvehicle selecting unit 222 selects one control target oncoming vehiclefrom the plurality of oncoming vehicles (step S703). The reason why onecontrol target oncoming vehicle is selected from the plurality ofoncoming vehicles is that the control for specifically preventingcollision between the vehicle 100 and an oncoming vehicle becomesuncertain unless the oncoming vehicle is identified accurately.

In step S703, the control target oncoming vehicle selecting unit 222first obtains, from the predicted time deriving unit 218, the collisionpredicted times (TTC) that elapse before the plurality of oncomingvehicles collides with the vehicle 100. Then, the control targetoncoming vehicle selecting unit 222 selects, from the plurality ofoncoming vehicles, the oncoming vehicle having the shortest TTC as thecontrol target oncoming vehicle for which collision with the vehicle 100is avoided. The oncoming vehicle having the shortest TTC is consideredto collide with the vehicle 100 earliest. Accordingly, the controltarget oncoming vehicle selecting unit 222 selects the oncoming vehiclehaving the shortest TTC as the control target oncoming vehicle.

When a plurality of oncoming vehicles having the same TTC is present,the control target oncoming vehicle selecting unit 222 obtains the firstdistances between the vehicle 100 and the oncoming vehicles in thetravel direction of the vehicle 100 from the distance deriving unit 220.Then, the control target oncoming vehicle selecting unit 222 selects theoncoming vehicle having the shortest first distance from the pluralityof oncoming vehicles having the same TTC as the control target oncomingvehicle. Of the plurality of oncoming vehicles present within the laneline detection range A, an oncoming vehicle having a longer distancefrom the vehicle 100 is considered to reduce its speed or change itstravel path to avoid collision with an oncoming vehicle having a shorterdistance from the vehicle 100. Accordingly, the control target oncomingvehicle selecting unit 222 selects the oncoming vehicle having theshortest first distance as the control target oncoming vehicle.

When a plurality of oncoming vehicles having the same TTC and the samefirst distance is present, the control target oncoming vehicle selectingunit 222 obtains the second distances between the vehicle 100 and theoncoming vehicles in the direction orthogonal to the travel direction ofthe vehicle 100, from the distance deriving unit 220. Then, the controltarget oncoming vehicle selecting unit 222 selects, from the pluralityof oncoming vehicles having the same TTC and the same first distance,the oncoming vehicle having the shortest second distance as the controltarget oncoming vehicle. The plurality of oncoming vehicles having thesame TTC and the same first distance travels in parallel and it isconsidered that the oncoming vehicle having the shortest second distanceis likely to collide with the vehicle 100 among the oncoming vehiclestraveling in parallel. Accordingly, the control target oncoming vehicleselecting unit 222 selects the oncoming vehicle having the shortestsecond distance as the control target oncoming vehicle.

When the control target oncoming vehicle selecting unit 222 selects onecontrol target oncoming vehicle or only one oncoming vehicle is presentwithin the lane line detection range A, the control target oncomingvehicle selecting unit 222 determines this oncoming vehicle to be thecontrol target oncoming vehicle for which collision with the vehicle 100is avoided (step S704).

In contrast, when no oncoming vehicles are present within the lane linedetection range A (NO in step S701), the control target oncoming vehicleselecting unit 222 determines that there are no control target oncomingvehicles for which collision with the vehicle 100 is avoided (stepS705).

Returning to FIG. 4, the control target oncoming vehicle selecting unit222 determines whether one control target oncoming vehicle is present(step S409). When one control target oncoming vehicle is present, theprocessing proceeds to step S410. When no control target oncomingvehicles are present, the processing proceeds to step S411.

When one control target oncoming vehicle is present (YES in step S409),the control target oncoming vehicle selecting unit 222 determines that acontrol target oncoming vehicle is present and sets this oncomingvehicle as the control target oncoming vehicle (step S410).

In contrast, when steps S402, S403, S405, S406, S407, and S409 produceNO results, the control target oncoming vehicle selecting unit 222determines that no control target oncoming vehicles are present and setsthe absence of control target oncoming vehicles (step S411).

After that, when a control target oncoming vehicle is selected, thesteering control unit 212 controls the steering mechanism 132 so as toavoid collision between the vehicle 100 and the control target oncomingvehicle. In addition, when a control target oncoming vehicle isselected, the braking control unit 210 controls the brake 160 so as toavoid collision between the vehicle 100 and the control target oncomingvehicle. This can control the vehicle 100 so as to avoid collisionbetween the vehicle 100 with only the control target oncoming vehicleselected by the control target oncoming vehicle selecting unit 222 amongthe oncoming vehicles traveling in the opposite lane.

As described above, the erroneous detection determination unit 226determines whether the oncoming vehicle detected by the oncoming vehicledetecting unit 216 has been erroneously detected based on the positionalrelationship between the position of the three-dimensional objectdetected by the three-dimensional object detecting unit 224 and theposition of the oncoming vehicle detected by the oncoming vehicledetecting unit 216. Specifically, when the oncoming vehicle detected bythe oncoming vehicle detecting unit 216 is present within the thresholdrange from the wall (center divider) detected by the three-dimensionalobject detecting unit 224, the erroneous detection determination unit226 determines that the oncoming vehicle detected by the oncomingvehicle detecting unit 216 has been erroneously detected. This canreduce the erroneous execution of avoidance control for avoidance ofcollision between the oncoming vehicle detected erroneously and thevehicle 100. Accordingly, collision between the vehicle 100 and theoncoming vehicle can be avoided accurately.

In addition, the above vehicle control method of avoiding collisionbetween a host vehicle and other oncoming vehicles, a program thatcauses a computer to function as the vehicle control device 140, astorage medium that stores the program, such as a computer-readableflexible disc, an optical magnetic disc, a ROM, a CD, a DVD, or a BD isalso provided. Here, a program is a data processing member described inany language or any description method.

Although a preferred example of the present invention has been describedwith reference to the accompanying drawings, the present invention isnot limited to such an example. Provided a person has ordinary knowledgein the technical field to which the example of the present inventionpertains, within the scope of the technical idea described in theclaims, the example of the present invention is intended to covervarious modifications and applications, and such modifications andapplications are intended to fall within the technical scope of thepresent invention.

The present invention can be used for a vehicle control device thatmakes control for avoiding collision between a host vehicle and anoncoming vehicle.

1. A vehicle control device comprising: a three-dimensional objectdetecting unit configured to detect a three-dimensional object providedbetween a travel lane in which a host vehicle travels and an oppositelane in which an oncoming vehicle travels; an oncoming vehicle detectingunit configured to detect the oncoming vehicle traveling in the oppositelane; and an erroneous detection determination unit configured todetermine that the oncoming vehicle detected by the oncoming vehicledetecting unit has been erroneously detected when the oncoming vehicledetected by the oncoming vehicle detecting unit is present within athreshold range from the three-dimensional object detected by thethree-dimensional object detecting unit.
 2. A vehicle control devicecomprising circuitry configured to detect a three-dimensional objectprovided between a travel lane in which a host vehicle travels and anopposite lane in which an oncoming vehicle travels; detect the oncomingvehicle traveling in the opposite lane; and determine that the oncomingvehicle detected by the oncoming vehicle detecting unit has beenerroneously detected when the oncoming vehicle detected by the oncomingvehicle detecting unit is present within a threshold range from thethree-dimensional object detected by the three-dimensional objectdetecting unit.